This invention relates to the attachment of a tool to a handpiece using a tightening tool moveably mounted on the operative end of the handpiece and more particularly to dental tools, particularly ultrasonic dental tools or instruments, and, more particularly, to a moveable structure on the forward end of an ultrasonic instrument handpiece for use in attaching an ultrasonic tip to the ultrasonic handpiece.
Ultrasonic devices and their tips are useful in carrying out a variety of dental procedures, such as tooth cleaning, preparation of cavities for filling and are particularly useful in preparing the canal of a tooth during root canal and endodontic procedures. Such ultrasonic dental tips are known, as shown in numerous patents of which U.S. Pat. Nos. 5,094,617, 5,133,661, 5,868,570, 6,722,882 and 6,811,399 and International Publication No. WO 00/74586 are examples. Most prior patents are directed to particular tip shapes to provide better visibility of the tooth and canal, improved maneuverability of the tip into the canal, operative end structure on the tip to provide smoother surfaces of the pulp chamber and prevent ditching, controlling depth of the tip so that the floor of the tooth canal is not penetrated, providing tips for removing, or not removing, different tissue (enamel, dentin, pulp stones) or tips of different materials, having different coatings or operating at specific frequencies for specific procedures such as cutting apically into calcified canals and for digging around posts that may have become embedded in the canal.
However, little attention has been provided to tools and procedures for easily and rapidly installing the tip on the handpiece or removing the tip for replacement with alternative functioning, or different size tips. The tips are typically threaded on to the handpiece requiring the dentist to use a separate wrench to grasp flat portions on the hub of the ultrasonic tip to remove the tip. U.S. Pat. Nos. 5,261,922, 5,318,570, 5,324,297 and 6,817,862 are representative of ultrasonic devices which have removable tips that have wrench flats formed on the hub of the tip for grasping with a separate wrench. Another mounting technique is shown in U.S. Pat. No. 5,776,155 which describes a prior art separate tightening tool applied to the tip hub and discloses a torquing device built into an adapter which remains over the tip hub and functions to retain the tip on the handpiece. U.S. Pat. No. 5,359,996 shows a tip with an end flange which is held against the transducer by a retaining nut slipped over the ultrasonic tip. This nut functions to hold the ultrasonic tip in place, does not function as a wrench and requires a separate wrench to apply and tighten the nut.
U.S. Pat. No. 4,038,571 to Hellenkamp shows an ultrasonic tool with a tip removeably threaded thereto. The tip base has exterior flats on its circumference. A rotatable cap on the front end of the tool has a hole in its front end to engage the flats on the tip when the tip base is inserted into the cap. When rotated, the cap functions to loosen or tighten the tip. During use as an ultrasonic cleaning tool the cap opening remains over the tip base which can result in biological materials becoming trapped within the cap.
My earlier issued patent U.S. Pat. No. 6,722,882, and FIGS. 1, 2 and 3 herein show an example of an ultrasonic dental handpiece and ultrasonic tips for placement thereon.